Knife sharpening devices generally include a pair of crossed abrasive rods or other common sharpening members constructed of compressed ceramic, graphite powder, or serrated hardened steel. A knife blade is sharpened by pulling it across the sharpening members. Many traditional knife sharpening devices are large or fixedly mounted and, thus, not portable. Examples of table-mounted knife sharpeners that employ crossed abrasive members, or other sharpening devices can be found in the following U.S. Pat. No. 620,050 to Poindexter, U.S. Pat. No. 1,032,910 to Jackson, U.S. Pat. No. 1,223,753 to Anderson, U.S. Pat. No. 1,451,526 to Bowles, U.S. Pat. No. 1,719,345 to Teitel U.S. Pat. No. 1,827,664 to Matthews, and U.S. Pat. No. 2,542,472 to Brinkley. U.S. Pat. No. 1,474,636 to Judd et al. and U.S. Pat. No. 2,473,702 to Carlin describe more complex table mounted devices that employ belts that sharpen the blade.
Although portable, hand-held knife sharpeners exist, they lack stability and are dangerous when used. That is, when many existing sharpening devices are used, the user's hand is positioned close to the knife sharpening member, which subjects the user's hand, wrist, or fingers to a risk of injury. For example, some current knife sharpening devices employ crossed abrasive rods supported by a handle, or other holding device. Although reasonably safe, these types of sharpeners have the disadvantage that they are difficult to support; i.e., they float in space and are only supported by the user's other hand, which can be dangerous. In addition, the lack of support may make it difficult to align the blade with respect to the sharpening members, which may cause inefficient or ineffective sharpening. More specifically, one important detail to properly sharpen a knife is to maintain a precise set angle for shaping a new edge on the blade. If the sharpening device is not stable, then any movement of the device during use will alter the angle of the edge applied to the knife, thereby resulting in inefficient or ineffective sharpening. In addition, the lack of support may make it difficult to align the blade with respect to the sharpening members.
Examples of handheld sharpeners can be found in U.S. Pat. No. 1,719,345 to Teital, U.S. Pat. No. 3,052,068 to Burgess, U.S. Pat. No. 4,494,340 to Carter, U.S. Pat. No. 4,502,254 to Carter, U.S. Pat. No. 4,530,188 to Graves, U.S. Pat. No. 4,751,795 to Jenne, and U.S. Pat. No. 6,846,299 to Ranicri. U.S. Pat. No. 5,165,251 to Lee discloses a handheld sharpening device that can be stabilized on a counter, but the device can still rotate about its contact point, which can influence sharpening characteristics.
Thus it is a long felt need in the knife sharpening field to provide a sharpening device that is portable, compact, and yet stable in use. The following disclosure describes an improved knife sharpening device that can assume a compact storage configuration and a stable use configuration.